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Topic: NHD-C0220Biz and Arduino/Teensy3.1 (Read 52398 times)

Hello, the I2C connection between the C0220Biz and my Teensy3.1 locks up when it is first initialized. Other I2c devices work fine, so I'll assume i am doing something wrong at initialization. Is there a library that will work for a teensy3.1 and a C0220Biz? It looks as if the address is 0x78. I have all the hardware connections as peer the Pin description and wiring diagram, and my supply volage to vdd is 3.3 regulated.

I'm sorry but unfortunately we do not have a library for the display with the teensy mcu. What we do have is the example code provided on our website, here: http://www.newhavendisplay.com/app_notes/NHD-C0220BiZ.txt.If you come across any libraries for the teensy that are designed to drive an ST7036 display controller, they should work for our display.As for your other question, is the display the only device present on the i2c bus when it is locking up? Have you tried using 10kOhm pull-ups?

I have swapped the pullups to 10K and then 2K, still no luck - I2C does not enumerate. I used another LCD I2C Backpack and it did work on I2C as well as other I2Cdevices so I know it's not the mp itself. I just want to ensure I have the proper connections - so as I look down on the LCD display, the mechanical drawing seems toindicate the connections from left to right are 8(c1-), 7(c1+), 6(Vout), 5(VDD), 4(VSS), 3(SDA), 2(SCL), 1(RST). However page 4 would seem to indicate the opposite.

OK, I tried our 2nd NHD-C0220Biz unit and it worked fine. So the issue with the first unit was that it was defective, it would not enumerate on the I2C bus at all. Used a 9K pull up on the working unit, that seems fine.

I'm sorry to hear about the issue you encountered. We have a set quality control process that is followed for every part so I'm not sure how this one got through, but we will make a note to double-check this type of issue during our QC inspections. I apologize for the inconvenience.